Preparation and Optimization of Steel Slag-Desulfurization Gypsum Composites Based on Interception of Arsenic-Contaminated Water at the Ground Surface

Based on the characteristics and effective components of steel slag and desulfurization gypsum, a new type of permeable reactive material was prepared by combining steel slag and desulfurization gypsum, and a simulation experiment of arsenic- and antimony-contaminated groundwater remediation was carried out. A combination of X-ray fluorescent, BGRIMM Process Mineralogy Analyzing System (BPMA), ICP-MS, and SEM-EDS detection and analysis methods was used to investigate the effects of steel slag particle size, desulfurization gypsum particle size, steel slag and desulfurization gypsum ratio, and steel slag-desulfurization gypsum mixed test block particle size on the performance of the permeable reactive wall to remove arsenic and antimony. The results show that a permeable reactive wall composed of steel slag (−4.75 + 1.18 mm) and desulfurization gypsum (−13.2 + 9.5 mm) in a 4:1 ratio achieved removal rates of 91.85% for As and 90.58% for Sb, reducing their concentrations below the drinking water standard. The purpose of using steel slag and desulfurization gypsum to intercept heavy metals and toxic ions in surface runoff was achieved. Arsenic was adsorbed, physically encapsulated, and lattice solidified by C-S-H gel. This research provides a cost-effective and environmentally friendly solution for the storage of steel slag and desulfurization gypsum while addressing heavy metal pollution in groundwater.